The RPG series that prevent me from being Final Fantasy hardcore fan. MegaTen Wiki not only offer game info but also huge database (Demonic Compendium) of various being that appear in game.

My main reason to post it here is that the site also feature great artwork by Kazuma Kaneko, his demon design is cool to extreme level. And since we are mecha fan, it worth to note that many of his design is mecha-ish (he also did Inhert in ZOE2 and three mech from SRW Alpha3). For instance, look at Vulcanus and Hermes.